Outer cover of rigid airships



April s, 1927. 1,623,681

K. HUERTTLE OUTER COVER OF RIGID AIRSHIPS Filed Sept. 12. 1925 2 Sheets-Sheet 1 fly. j 6, f a a f a April 5, 1927.

\ A K. HUERTTLE OUTER covER oF RIGID AInsHIPs Filed Sept. 12..1925 2 Sheets-Sheet 2 utmg the fabric used land Patented` Apr. 5, 17927.

` UNITED STATES PATENT oFjFIcE.

4KARL HUERTTLE, 0F AKRON, OHIO, ASSIGNOB soun x1 `emalumr.

T LUFTSCHIFBAU ZEPPELIN GESELL- u OUTER COVER 0F RIGID AIRSHIPS.'

Application led September 12, 1925, Serial No.. 55,904, and in Germany September 18, .1924.

My invention relates to rigid airships and more especially to the outer cover of such ships and the method of manufacturing the same.

5 Ri 'd airships have a hull structure into whic1 the gas bags are inserted and over which the shape giving outer cover 1s stretched. This outer cover has to sustain considerable stresses resulting from the a1r lo pressure and also from the tensionoccurring while it is bein fastenedjto the hull. On the other hand 1t should be as light as sible for the purpose of saving useful lift ofthe airship. Therefore itis neceary to pay special attention to the way of d1stribto the method of manufacturing the outer cover.

Accordin to my invention I` use a very light and t 'n fabric forthe main 'middle portions of the individual pieces of the outer cover., The edges of such ieces are reinforced by ribbons or strips o a much heavier and stronger fabric. Points where extraorary stresses occur may be also reinforced by a superposed layer of an elastic fabrlc, this elastic fabric having a higher degree of elongation than the main light fabric..A vThis causes a smooth and gradual transition of the stresses from the reinforcement to the $0 main fabric.

The reinforcing fabrics are connected to the main fabric by means of seams sewn by hand or better .by a machine. ere there are special reinforcing layers it will be use- !5 ful to have such seams running in the same direction with that of the stresses.- For example at the corners of the individual pieces of the outer cover where such reinforcing layers are very useful, the seams should ex- Il tend from the corners like rays.

, e seams connecting with the strips at the edges are along'and substantial] parallel to the edges. For the purpose ofy providing against a rent and 5 agamst the possible extension of a rent having occurred it will be advisable to have reinforcing strips at intervals running in cross direction to the edges. Generally it will be suilicient to make such cross strips short but v .1 at points of extraordinary stresses on the' outer cover, it may be useful tohave them extending lover the full width of the main portion. 4.

It is a further improvement to have the seams not running in straightlines but to the individual I the hull or to each other are situated inthe posadvantage that the li the .main portion make them curved in a wave-like manner or y other suitable form which will cause a better connection and also a better distribution of the stresses'.

As it is my aim to provide for an elastic connection it will be useful not to have the threads but to let their ends open freely.

The eyelets which are necessary for lacing pieces of the outerrcover to edge strips. But, according to my invention, such eyelets are stamped into the edge strip before this strip is sewn to the main fabric. This method is much sim ler than the usual way of stamping the piece of the outer cover, and it also has the ht and very sensitive mam fabric is treate more carefully. In connection herewith I consider it useful to fold the edge` situated in the double thickness.

aving given a general description of my invention I now want to point it out more in 'detail referring to the drawings which represent examples embodying my invention. Fig. 1 is a view on the inside of the outer cover, but partly broken up. Figs. 2 and 3 are cross sections through the edge of an individual piece of outer cover, on an enlarged scale, explaining the method of manufacture. Fig. 4 is the corresponding side view. Figs'. 5, 6 and 7 represent other modifications of the connection between main fabric and edge strip.

In Fig. 1 the ends of two pieces of outer cover A and B are shown at their longitudinal edges where they meet 4and are laced together. Also the-corners of the adjacent pieces C, D, E and F arerepresented.V Themain portion of every piece which is` made of the light fabric is designated by the letter a, while- If is the edge strip into which the eyelets y are stamped. The cor` ners of the pieces are lreinforced by special layers c. A`t those corners the connecting lseamsd are radially extending from the corner eyelet e. Cross strips f are provided at intervals for the purpose explained above.

In Fig.l 3 is shown how the strips b are of the seams knotted at their ends eye ets vin the finished strips so that the eyelets are A first folded and provided with a seam-Z adjacent the edge of each folded portiom T en vthe eyelets y are stamped in. I prefer to fold the strips b so .that legs of unequal length are attained. The main fabric a is I of Fig. 6, only lig) fa ric sewn strip being provided with ,the corners of said main put on top of the longer leg of strip b, but on its inner side as may be seen from Fig. 3. When it has reached the shorter leg of strip b a seam is sewn through a an the two legs of b. Above this seam fabric ais folded backwards so that a new seam 7c may connect tle two thicknesses of a with the longer leg o b.

In Fig. 5 seam k catches only one thickness of a and connects it with I 'In Fig. 6 an additional seam `m is sewn connecting two thicknesses -of a with two thicknesses o`f b. This seam m is made immediately after a has been folded and close to seam z.

The example of Fig. 7 corresponds to that seam k connects only one thickness of a to one thickness of b, similarly to the construction shown in 5.

I do not want to limit myself to the etails described or shown in the drawinfrs as many vvariations will occur to those skilled in the art.

What I claim is:

1. A piece of outer cover for a rigid airshi comprisin an inner main portion of lig t fabric an a stronger edge strip surrounding said main portion.

2. A piece of outer cover for a rigidairship comprising an inner main portion of light fabric, and reinforcing layers at the ornersof said main portion, the quality of said layers differing from the qualitv of said main portion.

8. A piece .'of outer cover for a rigid airship comprislng an inner main portion of light fabric, an edge strip of heavier fabric sewn to said main portion, and reinforcing strips running inwardly from said edge strip at certain intervals and also sewn to said main Jportion.

` piece of outer cover for a rigid airshi comprisin an inner main portion of lig t fabric an reinforcing fabric sewn to said main portion, said reinforcing fabric having a higher degree of. elongation than said main fabric.

10. A piece of outer cover for a rigid airship comprising an inner main portion of lig t fabric, reinforcing fabric sewn to said main fabric by means of seams, the ends of the threads of said seams opening freely without being knotted.

11. A piece of outer cover for a rigid airslii comprising an inner main portion of l1 t fabric and an edge strip of another fa. ric, degree of. elongation than said main fabric.

12. A piece of louter cover'for a rigid airship comprising an inner main portion of li v t fabric, and :in edge strip of another fa ric, said ledge strip beingv folded so as to form two legs of un main fabric being also fo ded but only at its edge, the turned over portionof the main fabric being connected to both legs of the edge strip by means of a common seam the straight portion of the main fabric and the 3. A piece of outer cover for a'rigid airlong leg of the edge strip being connected shi comprising an inner main portion of by a second seam.

light fabricvand an edge strip of heavier fa ric sewn to said main portion, \said edge strip being provided 4with eyelets.

4 A piece of outer cover for a rigid airshi comprising an inner main portion of t fabric, and an edge strip of heavier to said main portion, said edge eyelets.A 5. A. piece of outer cover for a rigid airshi comprising an inner main portion of lig t fabric, an edge strip of heavier fabric, and a seam connecting said two fabrics to each other. v

6. A piece of outer cover for a rigid air- Shi comprising an inner main portion of lig t fabric, and reinforcing layers of fabric at the corners of said main portion, said reinforcing layers being connected to said main portion by seams extending radially from said corners.

7. A piece of outer cover for a rigid airship comprising an inner main. portion of light fabric, reinforcing layers of fabric at portion, said reinforcing layers being connected to said main portion by sea-ins extending radially from said corners, the threads of said seams opening freel at their ends without being knotted. l 4

13. A piece of outer` cover for a rigid airship comprising an Inner main portion of li t fabric, and an edge strip of another fa ric, said edge strip eing folded so as to form two legs of un ual length, said main fabric being also fo ded but only at its edge, the turned over portion ofthe main fabric being connected to both legs of the edge strip by means of a common seam, the straight portion of the main fabric together with its turned over portion being connected again with both legs of the edge strip by a second common seam, a thir seam connecting the straight portions ofthe main fabric to the long eg of the edge strip.

14. Method o manufacturing pieces of outer cover for rigid airships which consists in sewing a special edge strip of fabric to a main middle portion of lighter fabric, by first folding said edge strip so as to form two legs of unequal length, by then making a longitudinal seam along the folding line, by sewing the edge of said main fabric to said secondl fabric having a higher ual length, said both legs of said edge strip by means of a common seam,v by turning over said main fabric along said common seam, and by sewing it tothe loncer leg of said edge strip by means of a thir seam.

15. Method of manufacturing pieces of 5 two le outer cover for rigid airships which consists in sewing a speclal edge stri of fabric to a main middleportion of lig ter fabric, by first folding sald edge strip so as to form of unequal length, by then making a longitudinal seam along the folding line, by sewing the edge of said main fabrlc to both lengs of said edge strip by means o1' va common seam, by turning over said maln strip, and by making a fourth seam connectlng the turned over main portion of said light fabric to the longer leg of said edge strip,

KARL- HUERTTLE. 

